Apparatus for heat-treating substances packed in sealed receptacles



APPARATUS FOR HEAT TREKKING `SUBS'I.'A{GI:`|S PACKED 1N SEALED RECEPTACLES Original, Filed Dec. 5, v1924 ma l @19" \4\ 'p IiHIIiiIi 1l: *g4 Hl, lll@ WH:

Patented Mar. 9, 1926.

UNITED STATES PAIENT 'risica OriginalV application filed December 5, 1924, Serial No. 754,126. Divided and'this application filed April 11,

1925. Serial No'. 22,613.

fl 1`o all whom t may concer/t.'

Be it known that I, Nn-LsoN H. Foons, a citizen of the United States, residing at Preston, in the county o-f Caroline and State of llflaryland, have invented certain ne-w and useful improvements in Apparatus for Heatllreating Substances Packed in Sealed Receptacles, and l do hereby declarethe following to ,be a full, clear, and exact'description of the invention, such as will enable others skilled inA the art to which it appertains to makeand use the same.

rl`his invention has tor its object to provide an improved method of heat-treating foods in sealed receptacles, such as tin cans, whereby the cooking period may be easily controlled and `the receptacles cooled to reduce the internal Vpressure therein before being discharged into the atmosphere.

In methods where the receptacles are progressed through a retort along a delinite path it has been proposed to control the cooking period by ejecting lthe receptacles from the retort at a selected point or points in their path of travel. This manner of control notonly involves the employment of more or less complicated and consequently expensive machinery, but. also necessitates the discharge of the receptacles into the atmosphere directly from the heating medium with consequent danger of springing of the seams of the cans and resultant loss of the product, particularly where the high cooking temperatures are employed.

According` to my invention, the sealed re` ceptacles are progressed along a path of delinite length within the retort irrespective of the cooking period and are cooled before discharge from the same. rlhe retort is filled with superposed fluids maintained at different temperatures, the cans being passed from one fluid to the other in their course of travel through the retort, To control the cooking period it is merely necessary to raise the level of the fluid of lower temperature.

inasmuch as the cans are progressed through the retort at a delinite rate of movement, it follows that they will remain in the lluid of higher temperature a greater or lesser time depending on the depth of the hotter fluid, which depth is controlled by the level of the cooler fluid. The fluid of lower temperature is preferably water and obviously constitutes the cooling medium ;J- the fluid of higher temperatures is preferably a gaseous medium, such as steam but may be a heat-,ed iixed gas, such as air, or afmixture of steam and air. The apparatus for carrying o-ut my improved process is extremely simple necessitiating7 outside of the can-car- -ryingmechanism, relatively sim-ple means for maintaining the heating and cooling lfluids `at proper levels and temperatures.

ln the accompanying drawing, Fig. l is .a part sectional and lpart diagrannnatic elevation of a cooker and cooler in conjunction with which my improved*process may be practiced.

Fig. 2 is a botto-1n plan viewof one group o-f pipes through which the heating-medium is entered into the apparatus shown yin Figi.

ln the drawing Fig. l indicates generally a retort or ta-nk provided with a gauge glass tube for indicating the level of the liquid in the retort; 3 ai water supply pipe; 4a pipe or conduit for supplying heating medium to the retort, said pipel having valved lateral extensions each in connection with a group of horizontally disposed ypipes generally indicated at 6 and perforated on their bottoms. ln lilling and niaintaining` the retort or tank with the heating medium, the latter will be admitted through' that group or 'bank of pipes `6 which is closest to the' level of the liquid maintained in the tank, thereby ob viating any dead or cold space above the cooling liquid.

The desired level of the cooling liquid yis maintained by providing a series ofsteam traps, generally indicatedV at 7, at different levels, the traps permitting the cooling liquid to flow out therethrough but not steam, as will be readily understood, the Waste pipe in connection with said traps being indicated at 8, each trap having a controlling valve 9 exterior thereof to permit the liquid level to be raised to the next higher trap, as will be readily understood.

The retort or tank is provided with any suitable form of can-conveying means which will permit the cans to be moved at a uniform rate from one level to another in the tank through the heating and cooling mediums. For simplicity of showing no Specilic can-moving means is shown but only the path which the cans will followV in their progress throne-h the tank such path being indicated at lOby a line of cans. l/Vhen the gaseous medium is maintained under pressure greater than atmospheric pressure the cans may be entered into the retort or tank through a rotary valve 11, and be vdischarged therefrom byi a similar` valve 12. However, when the process is practiced without maintaining the gaseous heating medium under pressure, any suitable means for feeding the cans and receiving them from the endless conveyor may be employed. In the present showing of the cooker and cooler the cans after passing through the kcooling liquid at the bottom of the tank are shown as passing upwardly through ak well 13 formed by a partition 14 and thence outwardly through the discharge valve 12.

It will now be appreciated that in its broadest aspect my invention contemplates the cooking and cooling of substances within sealed receptacles by passing the receptacles through superposed iiuids while maintaining the fluids at different temperatures. That when steam is used as the heating medium temperature of the same may be raised by maintaining the steam under pressure greater than atmospheric; that the method of controlling the cooking period is not dependent on maintaining a pressure greater than atmospheric pressure within the tank; and that the invention is just as applicable to a sc-called open air cooker and cooler as to a pressure cooker and cooler. lllhen the cooling medium is water and the heating medium is a gaseous substance the receptacles will, of course, be progressed through the tank from the top to the bottom thereof inasmuch as the heating medium will then overlie the water..y It may, however, be found desirable to utilize the water as the heating medium and to maintain a suitable cooling medium thereabove for cooling the cans, in which event the cans would obviously be passed from a lower level to a higher level, namely: through the cooking water at the lower level and the cooling medium thereabove. It is also possible to use nonmiscible liquids, one of which will serve as the heating medium and the other the coeling medium.

The desired temperature of the cooling water is kept up by supplying the cooling water through the pipe 3 and the heating` medium is maintained by supplying the same through the conduit 4, as will be readily understood. The gauge glass tube affords a ready means for Idetermining the level of the liquid within the tank.

The appended claims are intended to define what I kconsider to be the various novel features of the invention.

This application is a division of my application Serial 754,126, iiled December 5,

Vhat I claim is:

1. In a device for cooking and controlling the cooking period of substances within sealed receptacles, the combination with a tank, a body of relatively cooling liquid partially filling the tank, a body of relatively hot fluid superposed on the body of cooling liquid, a path for the receptacles extending from the upper to the lower level of the tank, and means for maintaining said bodies at predetermined levels.

2. In a device for cooking and controlling the cooking period of substances within sealed receptacles, the combination with a tank, a body of cooling water partially lling `the tank, a body of gaseous heating medium superposed over the water, and a continuous iixed path of different levels along which the receptacles are passed through `the heating and cooling mediums.

3. In a device of the character described, the combination of a tank, a continuous path extending from the top to the bottom of the tank, a body of cooling water in the tank, a l

body of steam overlying' the body of water, means including steam traps for maintaining the water at a given level, and means for keeping the tank filled with steam.

In testimony whereof I afx my signature.

NELSON H. FOOKS. i 

